State the law of conservation of energy in your own words

A marathon runner completes a 42.188–km course in 2 h, 36 min, and 12 s. there is an uncertainty of 23 m in the distance travele

timurjin [86]

The percentage uncertainty in the distance is 0.054%.

Uncertainty in a measurement measures the deviation of the measured values from the true value.

The distance d can be expressed in the form d+/-Δd, where Δd is the absolute uncertainty in the measurement of distance.

The percentage uncertainty is given by,

$Percentage uncertainty=\frac{\Delta d}{d} *100$

The uncertainty in the measurement of distance is 23 m. Express the uncertainty in km.

$\Delta d =\frac{23 m}{1000 m/km} =0.023 km$

Calculate the percentage uncertainty in the distance.

$\frac{\Delta d}{d} *100 =\frac{0.023 km}{42.188 km} *100=0.054 %$

Thus, the percentage uncertainty in the measurement of distance is 0.054%

4 0

3 years ago

Two blocks of masses mA and mB are connected by a massless spring. The blocks are moved apart, stretching the spring, and subseq

WINSTONCH [101]

Answer:

Part a)

$\frac{v_A}{v_B} = -\frac{m_B}{m_A}$

Part b)

$\frac{K_A}{K_B} = \frac{m_B}{m_A}$

Explanation:

Part a)

As we know that initially the two blocks are connected by a spring and initially stretched by some amount

Since the two blocks are at rest initially so its initial momentum is zero

since there is no external force on this system so final momentum is also zero

$m_Av_{1i} + m_Bv_{2i} = m_Av_A + m_Bv_B$

now for initial position the speed is zero

$0 = m_Av_A + m_Bv_B$

now we have

$\frac{v_A}{v_B} = -\frac{m_B}{m_A}$

Part b)

now for ratio of kinetic energy we know that the relation between kinetic energy and momentum is given as

$K = \frac{P^2}{2m}$

now for the ratio of energy we have

$\frac{K_A}{K_B} = \frac{P^2/2m_A}{P^2/2m_B}$

since we know that momentum of two blocks are equal in magnitude so we have

now we have

$\frac{K_A}{K_B} = \frac{m_B}{m_A}$

7 0

3 years ago

PLS PLS PLS PLS PLS HELP

stepladder [879]

Answer:

An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. Electromagnets usually consist of wire wound into a coil. A current through the wire creates a magnetic field which is concentrated in the hole, denoting the centre of the coil. The magnetic field disappears when the current is turned off. The wire turns are often wound around a magnetic core made from a ferromagnetic or ferrimagnetic material such as iron; the magnetic core concentrates the magnetic flux and makes a more powerful magnet.

Electromagnets

When an electric current flows in a wire, it creates a magnetic field around the wire. This effect can be used to make an electromagnet. A simple electromagnet comprises a length of wire turned into a coil and connected to a battery or power supply.

5 0

3 years ago

The same strength force was exerted in the same direction on both Object A and Object B. Why did Object A go faster than Object

VashaNatasha [74]

Answer:

$m_B > m_A$

the mass of body B must be greater than the mass of body A

Explanation:

Newton's second law establishes a linear relationship between the force, the mass of the body and its acceleration

F = m a

a = F / m

Let's analyze this expression tells us that the force is of equal magnitude for the two bodies, but body A goes faster than body B, this implies that it has more relationships

a_A > a_B

$\frac{F}{m_A} > \frac{F}{m_B}$

$m_B > m_A$

Therefore, for this to happen, the mass of body B must be greater than the mass of body A

6 0

3 years ago

The dentisty of an object relies on both the _________ of the object.

Daniel [21]

Answer:

Density is determined by an object's mass and volume.

Explanation:

If two objects take up the same volume, but one has more mass, then it also has a higher density.

7 0

3 years ago